Field
Embodiments described herein generally relate to a temperature control system for a substrate processing system, and more specifically, to a temperature control system for regulating the temperature of a substrate support assembly disposed in a substrate processing system.
Description of the Related Art
Flat panel displays (FPD) are commonly used for active matrix displays such as computer and television monitors, personal digital assistants (PDAs), and cell phones, as well as solar cells and the like. Plasma enhanced chemical vapor deposition (PECVD) may be employed in flat panel display fabrication to deposit thin film on a substrate supported within a vacuum processing chamber on a substrate support assembly. PECVD is generally accomplished by energizing a precursor gas into a plasma within the vacuum processing chamber, and depositing a film on the substrate from the energized precursor gas.
During deposition, the plasma within the vacuum processing chamber heats the substrate and the substrate support assembly. The plasma may cause the temperature of the substrate and support assembly to have a temporal temperature increase or spike (e.g., about 30-50° C. increase, or 20%-30% temperature increase from 90° C.). Such a large temperature increase of the substrate and support assembly undesirably causes process variation and/or overheating of the substrate.
Thus, there is a need for an improved temperature control system for a substrate support assembly.